Brief comments on impacts that scientific studies have pointed out as plausible, as consequences of modifications being proposed in the Brazilian Forest Code are given here (in two postages). The original articles were published in BIOTANEOTROPICA, vol. 10, n.4, 2010, a publication of the “FAPESP – Fundação de Amparo à Pesquisa do Estado de São Paulo”. [N.B. bold types are of my responsibility]
In this first postage we will present the summaries of impacts on fish, amphibians, reptiles, and birds.
1. Changes in the Brazilian Forest Code: potential impacts on the ichthyofauna (Lilian Casatti).
In this paper is presented an analysis of possible impacts that the reduction of native vegetation, especially riparian forests, can have on the fish fauna. Three sets of primary functional aspects performed by riparian forests are discussed: transferring of solar energy to the aquatic environment, trapping nutrients and sediments that enter the rivers and transfer of organic material between the terrestrial and aquatic environments. Any modification which results in further loss of native vegetation, in permanent preservation areas or in protection reserves, may generate losses of species, faunal homogenization and reduction of fish biomass.
2. The review of the Brazilian Forest Act: harmful effects on amphibian conservation (Luís Felipe Toledo)
In the last months there is a growing discussion in Brazil about a new Brazilian Forest Act (Código Florestal). This new proposal, in substitution to the current Act, includes modifications which will affect negatively natural populations of amphibians. Besides the deleterious impacts upon amphibians, it will also harm the national and international human populations. Among the possible effects, in consequence of the associate amphibian population declines or complete loss, we cite the increase of agricultural production costs, loss of primary sources of compounds for the medical industry, generalized ecological disequilibrium, eutrofication of water bodies, increase in the costs of water (for humans) treatment, increase of agricultural plagues, and increase of insect borne diseases. All these effects are of high relevance, even more if we consider the population declines of amphibians, the most threatened terrestrial vertebrate group in the world. Therefore, we propose that if a new Forest Act must be prepared, that it should be based, besides in unlikely immediate economical benefits to farm owners, in scientific knowledge which benefits nature conservancy, economy, health, and human welfare.
3. Potential impacts of changes in the Brazilian Forest Code on reptiles (Otavio Augusto Vuolo Marques; Cristiano Nogueira; Marcio Martins; & Ricardo Jannini Sawaya).
We evaluate the potential impacts on Brazilian reptiles (721 species already described), if the proposed changes in the Brazilian Forest Code are approved. The possibility of environmental compensation (a legal obligation in case of disturbance of natural habitats) in basins or micro basins different from that in which the disturbance occurred would have harmful effects on reptile diversity. Some reptile genera include species that rarely co-occur in space. Thus, conservation action planning based on naturally smaller scales, such as micro basins, is most suitable to maintain species composition across large regions. The proposed changes also include the removal of mountaintops as Areas of Permanent Preservation (APP, areas which must be permanently protected, despite the fact that they are not part of a park), as well as a reduction in the width of gallery forests and protected riparian habitats (which are APPs). Many Brazilian reptiles are restricted to high elevation areas, whereas others dwell only or mostly in gallery forests and riparian areas. Thus, the habitat loss that would result from these two changes could make some reptiles vulnerable to extinction. The proposed changes also include allowing the restoration of the Legal Reserves (LR, the reserves of natural vegetation which landowners have to keep in private areas) using exotic plant species. There are evidences that many Brazilian reptiles are not able to persist in human-modified environments like forests composed of exotic trees. The proposed changes also allow the compensation of disturbances imposed on LR inside existing protected areas. However, existing protected areas are not sufficient for the maintenance of reptile diversity in Brazil (mainly because many species have restricted distributions). If approved, the proposed changes in the code will impose significant negative effects on the Brazilian reptile fauna, an important component of the country's natural heritage. Furthermore, unknown molecules with potential for pharmaceutical use could also be lost.
4. Potential impacts of the changes proposed in the Brazilian Forest Code on birds (Pedro Ferreira Develey & Tatiana Pongiluppi)
Proposed changes in the current Brazilian Forest Code can lead to the reduction of native vegetation (forests, grasslands and wetlands) impacting directly many bird species. In Brazil, 17 globally threatened species are dependent of riverine forests and eight of these are restricted to the Brazilian territory. A decrease in the width of the area that should be protected as Permanent Preservation Areas (Área de Preservação Permanente - APP) can lead to significant population losses that would put at risk the integrity of populations and, in some cases, the survival of species. In fragmented landscapes, the APPs function as corridors, allowing the dispersion of birds through the matrix. Legal Reserve (Reserva Legal) areas should be maintained complementary to APPs, as the avifauna composition varies in areas located near and far from water bodies. Environmental heterogeneity is crucial to the maintenance of the bird community integrity. Even small patches of forest are important to the avifauna, working as stepping stones that, like the corridors, enable forest birds to move across the landscape. Birds are important predators, dispersers, and pollinators in agricultural ecosystems: in the Tropical region, areas with high bird diversity are significantly correlated with the highest rates of arthropods' removal, including those considered pests. Thus, proposed changes in the current Forest Code may represent a negative impact not only in relation to biodiversity, but also in regarding the agricultural production.
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